Functional genomics relies heavily on high-throughput and the various tools of bioinformatics to identify gene sequences of potential interest from the many molecular biology databases now available. There is a continuing need to identify and characterise further genes and their related polypeptides/proteins, as targets for drug discovery.
Recently, the first human protein histidine phosphatase (PHP1) has been identified. The enzyme was isolated from rabbit liver extracts and characterized. In human cell lines PHP1 is displayed in the cytoplasma. Functional studies with the orthologue protein in C. elegans showed a neuronal localization. The C. elegans homologue of PHP1 has been localized in motor- and pharyngeal sensorineurons MC, M3 and I2. The analogy from a nematode's pharynx to the human heart is described (PNAS 1998 95, 5072–5) thus, PHP1 and ligand could be relevant for various cardiovascular diseases.
In the current application protein interaction studies with PHP1 have been used in combination with DNA sequencing technologies and bioinformatics to identify gene sequences and gene functions that are ligands and interaction partners of PHP-1 on a molecular level.